Yes, you can file now and you should so as soon as possible. You can use the 2017 edition of TurboTax to file your 2017 Louisiana state tax return.
how do i get the 2017 tax forms for the state and continue from my federal ?
You will need to download the desktop software for 2017 to prepare a 2017 state return, which will have to be printed, signed and mailed.
To finish a prior year return started in TT online:https://ttlc.intuit.com/questions/2559403-how-do-i-finish-a-prior-year-return-that-i-started-in-turb
When you mail a tax return, you need to attach any documents showing tax withheld, such as your W-2’s or any 1099’s. Use a mailing service that will track it, such as UPS or certified mail so you will know the IRS and/or your state received the return.
The other (cheaper) option would be to obtain the 2017 state form from your state's tax website and prepare it by hand, then mail it in. You will need to have a copy of your 2017 federal return in front of you to refer to.
https://ttlc.intuit.com/questions/1901670-how-do-i-contact-my-state-department-of-revenue